|A highly regarded expert|
I've only run into 2 or 3 players who play like that, and I've played with hundreds. They're a drag to play with. It's like encountering a sociopath.
Most people understand that it's a team effort. Everybody gets to shine at some point or another.
Most people who are just starting out will take advice from the more experienced. I GMed a few PFS games (I really don't like to GM, but it was just starting, and there weren't enough GMs), and played with total virgins to Pathfinder. The key was to make it fun enough, they'd want to play again. Some came back, others didn't.
While I don't play PFS there anymore, it's going strong without me.
Present it as a game of teamwork, and players get the hint.
If somebody dumped con, then realized their mistake, I'd let them reconsider. I still play because people were (and still are) patient with me.